- Calcite on Quartz var. Amethyst ps. Calcite
- Peregrina Mine, Guanajuato Mun., Guanajuato, Mexico
- Small Cabinet, 8.4 x 5.9 x 3.6 cm
- Ex. David and Emily Stoudt; Eric Asselborn
Calcite takes on different crystal habits based on the formation conditions. Guanajuato localities are famous for their multistage Calcite and Amethyst specimens. This double-sided specimen does a fantastic job of displaying this quality. One side has tiny Amethyst crystals epitaxially replacing bladed primary-stage Calcite. The other side has limpid, late-stage scalenohedral, and twinned Calcites. This later stage of Calcite fluoresces a brilliant orange-pink best under shortwave light. There is damage on the amethyst side of the specimen; however, the other side beautifully displays a 3.4 cm Calcite twin. This piece is both displays well and tells a great story about the geology of the deposit. Unusual , and aesthetic miniature!